Photographic copying device



- Filed Jan. 51, 1958 p 3, 1963 F- BIEDERMANN ETAL 3,102,463 PHOTOGRAPHIC COPYING DEVICE 3 Sheets-Sheet 1 32 I 2+ I 40 31 ill; [Ill //1 [Ill Q Z INVENTORS Friedrich BIEDERMANN Rizhard W/CK BY p 1963 I F. BIEDERMANN ETAL 3,102,463

PHOTOGRAPHIC COPYING DEVICE Filed Jan. 31. 1958 3 Sheets-Sheet 2 511+ s2- 5: His? INVENTORS Friedrich B/EDERMANN, Richard WIC K flaw m p 1963 F. BIEDERMANN EI'AL 3,102,463 PHOTOGRAPHIC COPYING-DEVICE Filed Jan. 31, 1958 s Sheets-Sheet s 01 79 Lyra INVENTOR5 Friedrich BIEDERMA'NMRichard WICK 3,102,463 PHOTOGRAPHIC COPYING DEVICE Friedrich Biedermann, Unterhaching, near Munich, and

Richard Wick, Munich, Germany, assignors to Ag'fa Aktiengesellschaft, Leverkusen, Germany Filed Jan. 31, 1958, Ser. No, 712,571

Claims priority, applicationGermany Feb. 7, 1957 1 'Claims. (Cl. 95-73) g The present invention relates to photographic copying devices such as photographic enlargers. f

In devices of this type it is necessary tor the operator to adjust several parts before a proper copy of a transparency can be made. (In this specification and the claims which follow the term transparency signifies' not' only color transparencies, but also a black and white negative.)

For example, where the device includes an automatic ex- 'posure control which is adjusted in accordance with the 1 average density of the transparency, it may be necessary to adjust the control further in the case where important parts of the transparency have a light density substantially different from the average density, and adjusting devices for making such adjustments are known. It is also known to provide a means for automatically returning such an adjusting device to a zero or rest position after each exposure. Therefore, with such a construction it is necessary to reset such an adjusting device for each exposure, and this requirement creates considerable inconvenience'in the case Where a series of identical copies of the same transparency are to be made, because the adjusting device requires resetting for each copy even though no other adjust ice i 2 V to its construction and its method of operation, together with additional objects and advantage thereof, will be best understood fromthe following description of specific embodiments when read in connectionswith the accompanying'drawings, in which:

FIG. 1 is a perspective viewof a copying frame of a I photographic enlarger; I v

FIG. 2 is a fragmentary partly sectional elevational view illustrating part of an automatic return structure located within the housing-likeframe of FIG. 1;

FIG. 3 is a fragmentary partly sectional side elevational view' showing the latching and releasing structure for releasably holding the light-sensitive copy sheet on the support of FIG. 1; l

FIG. 4 is a wiring diagram of the arrangement of the present invention;

FIG. 5 is a fragmentary which makes contact copies; and 1 FIG. 6 shows part of the electric circuit used with the structure of FIG. 5. 3

FIG. 1 shows the housing-likeicopy frame 1 of a photographic copying device in the term of an enlarger which is not further illustrated. The frame 1 forms a support for the light-sensitive copy sheet which is located on the top Wall of the support 1. This support 1 is located on the base plate of the enlarger and its top Wall is formed in part-by the plate 2 through which light is capable of passing and which serves as a support for the light-sensitive copy paper. Beneath the plate 2 is located a photoelectriccell of 'a'known and unillustrated exposure control device. This photoelectric cell receives the light One of the objects of the present invention is to provide a photographic copying device which includes structures for automatically operating diiferent parts of thedevice intthe proper sequence so as to greatly decrease both the required manual operations as well as the possibility of error, as compared to conventional photographic copying devices.

It is also an object of the present invention to provide in a photographic copying device which requires a plurality of operations to be performed when a transparency is newly placed in the device a means which will automatically perform one of theseoperationswhen another of these operations is carried out;

A further object of the present invention 'is to provide a photographic copying device which will automatically reset an adjuster of the exposure control to its zeroposi 1 tion only when one transparency is exchanged for another,

so that any desired number of identical copies may be made'from the same transparency without the necessity of resetting such an adjuster after each exposure as is required at the present time in known copying devices.

' pair of manually turna-ble knobs .4 and 5 Which are turned to adjust a pair of unillustrated otentiometers, respectively, located in the circuit of the exposure control device, these potentiometers being adjustedin such a Way that the light source is deenergized automatically when a preselected amount of light has impinged on the photoelectric cell. The knob 4 is turned to adjust the control in ,accordance'with the sensitivity of the particular c PY Paper Which is used, while the knobSis'turnable in both directions from a zero position inorder to correct the setting of the automatic exposure control de- With the above objects in view the present invention includes in a photographic copying device a pair of means which are required to be operated when one transparency is exchanged for another. In accordance with the present invention one of these means, when it is operatedin connection with the placing of another transparency in the device, automatically actuates at least part of the other means.

appended claims. The invention itself, however, both as the exposure time with respect to the exposure time required for the average density of the transparency in those cases. wherethe transparency includes significant parts whose density diiiersfrom the average density. I

As may be seen from FIG. 2, in the interior of the housing which forms the support 1 there is a shaft 6 to Y which the knob 5 is fixed so that the shaft 6 is turned upon turning of the knob 5, and this shaft 6 fixedly carries a toothed disc 7. v A projection 9 extends into the teeth 8 of the disc 7,, and this projection 9 forms part of a lever 12 turnable about a stationary pin 10 and urged by the spring 11 toward. the disc so that the spring 11 urges the tooth 9 into engagement withthe teeth 8. Thus, the toothed disc 7 and spring-urged lever llcooperateto minain the shaft 6 and the knob 5 in the angular position to whichthey have been turned by the operator. The lever 12 carries an armature 13 which cooperates with an electromagnet 14 carried by a bracket 15 which is p partly sectional elevational I view of a different embodiment of the present invention where the present invention is applied to a copying device fixed to the ,3 ofithel housing. When knob ,5 is

manually turned theteeth S of the disc 7 cause moveactionof springf l-l. As soon as one of the teeth 8 has passed the projection 9, the lever 12 with" its projection '9 returns into the'nexofollowing gap between the-teeth 1 J 3 of disc {7 by action of the spring 11. I

V A pair of arms "Mandi? {are freely. turnable on the I f shaft 6and a wirespring18- iseoiled about the shaft 6 N and"hasa pair of free ends 'respectivelyengaging the arms 16 and-17' in the manner shown in FIG. 2 for urging-these arms toward' each "other in amanner which decreasesthe angle, included "thereb etweenj; 'iThe' arms 16' and 17; respectively engage thepins 1 9 and 20* Whichf v are respectively fiXedT-tothe disc-7 and the support 1'.

Thus-the spring 18 urges the knob 5 to a zero position,

when thelever 12 is turned away fromithe disc 7, where the pin-191s located along .a straight line in the plane of 2 whichinterconnects the axis of the shaft 6 with the axis ofthe stationary pin 20.

- A copy. sheet holderf2l; which is only shown schemat-. ically in FIG; 1 and which can be provided with masks, is turnably supported by' theshaffZZ for movement down wardly trom the rest; position shown in FIG. "1 v toa po s -vides the light for examining a transparency. The light source for examining purposes is preferably the same as sition nexttothe'top wall of the support, 1 for holding the copysheet in place. The shaft 22 extends parallel 1 ".,'to the topvsurfaceof the support 1 and is carried by a ,pair ofibosses',23..and, 24 which are fixed tojthetop surface of the suppor't 1. The holder 21.is fixed to the shafit 22' for turning movement therewith and this shaft ;Z2.is =t-urnably supported by horizontal bores. formed in p {the bosses 23 and 24. The shaft 22 extendsfthrough and .beyondtheboss24, and at its end beyondtheboss 24 the shaft 22 is "fixedly connected with famanually operable lever 25 which is engagedby the'operator and turned downwardly'in a counterclockwise direction, as viewed Y in FIG. 3',:'for-nioving the holder 21 fromits rest to its I holding position. A pair of springs 26 and- 27 are coiled I "about the shaft 22 anden-gage the holder 21 and the top surface of the support 1 for urging the holder 21 upwardlyfromits holding position to its rest position, and any suitable stops may be provided for determining. therest positiongof the holder 21; "The operator upon engaging wthe lever 25 turns the, holder21 downwardlyto its hold- Y ing position against the torso ofthe springs 26 and 27.

arcades the, latter is energized. A

member 39 is fixed to the v u armature 38-and extends leftwardly1beyond' the same, rnent of projection 9 out. of the teeth 8 against the v as viewed in FIG. 3, to engage .the bottom end of a motion transmittingpin d1v which extends sl-idably through a sleeve 40 which is carried by a top wall of the support "Lin an opening-of this top wall. The topend' of the pin 41 engages the underside of the tilt member 32 in the y manner shown in FIG. 3. 1 net 35 is energized the armature 38together with the" member 39 will be turned about the pivot pin 37- ina" Thus, when the electromagclockwise direction, as viewed in FIG. 3, to raisethe'pin 41 which, during its-upward movement, turns the tilt member 32 in a counterclockwise direction, as viewed in FIGQ3, so as to release the latch means. 7

Thetorque applied to the shaft 22 by the operator, through the lever 25 is sufficiently largeto permit the shaft 22 to twist slightly and then theoperator presses the lever 25 downwardly beyond the position it has reached when ,the holder 21is located in its holding position. "further turning of the arm 25 causes a projection 42-fixed y thereto to engage and close a switch 43 (FIG. 1). This 'A latchin'gmeans is carried by the'support 1 and c'of operates with th'e lever or arm .25 for releasably holding 'the'hold-er 21 in its holding position. This latching means includes aflatch; member 29 fixedly carried by a tree end portion28'of the lever 25. Thefsupport 1.fixedlycarries at its-top surface a pivot pin 30 which tiltablysupportsianelongated tilt member .32'urged by the spring 31 (FIG. 3) to turnfabbut thepivbt 30 in a clockwise the operator toturnthe tilt member32 in a counterclockwise direction, as viewed in FIG. 3, against the force of the spring 31', so as to turn; the hook member 33 away from the latch member 29 and thusrelease the older Zljtothe springs '26 and 27 which form amoving -;means for moving-the 7' its rest position. 1 I

i Also, as is shown in FIG. 3, an electromagnetic means may-be provided forre1easingthelatch means, and this holder from. its holdingback to switch 43 when it closes starts the operationofthe exposure controldevice and startsthe exposure itself. p

" The support 1 also carries-a manually operable switch 44 which is used for turning on and oil a lamp which-prothe light source used for the actual exposure.

ing purposes is indicated :at45 in: thewir-ing diagram of -FIG."4.- As may be seen from FIG; 4 the electrical cir- I cuit includes thele'ads 46 and 47 which connect the lamp 45 with'the usual source of alternating current. The circuit provided by the leads 46 and 47 with the lamp 45 includes the switch 44 for actuating the examining, as well as a resistor 49. A relay 5.0 is connectedin parallel with the lamp 45. and switch 48.

Also, the leads 46 and47 are connected throu'gha Mrectifier 51, which cooperates with a filter condenser 51a,

to-the electromagnet 14 of the adjuster of theexposure control, this adjuster being shown in FIG. Zand' described above. The magnet 14 is connected in series with a condenser. 52 through :a switch a which is controlled by the relay 50. The switch 50a can turn to the positionof FIG. 4 where it connects the resistor 53. with the condenser 52. I

The circuit of -th e rectifier 51 further includes the electromagnet 35 described above in connection with FIG. 3

electromagnetic means includes. the, electromagnet '35 which'is mounted in the interior; of the housing 1 on a suitable carryingdevice vfhi'w hich also carries a pivot pin 37 on which an'ar matnre 38 is pivotally supported'to be "pulled downwardly toward the electromagnet 35 wh'en denser 54 which is capable of being connected with 'a resistor 56 when the switch 55 is turned to the left from the position shown in FIG. 4. A further ,resistor57 is provided to be connected into the circuit of the magnet 35 p, and condenser 54 when theiswitch 50b is pulled to the left, as viewed in FIG. 4, by the relay 50. 7

: ,Adarkroom lamp58, together with its switch '59 are unillustrated exposure control device. 2 The above described structure operates-as follows:

' After a given copying process has been completed the a movable partsfof the; device and the electrical circuit take the position shown in FIGS. 1, 2. =a11d 4, and it willlbe seen that during this previous operation the knob 5 was; '7

located away from its zero position at a certain setting for adjusting the exposure control device. The lever 12. holds the disc 7 at the angular position to which it was previously turned by the knob 5.

The previously copiedt-ransparency is removed and'the next transparency which is to be copied is placedon the unillustrated transparency carrier of the enlarger. Then,

Such i so as to energize the lamp 45. It will be noted from FIG. 4 that at" this time the resistor 49 is located in the circuit of the lamp 45 so that it does not provide a light which is as intense as that provided with the lamp 45' is I used for the actual exposure. It will be'noted that the closing of the switch 44 simultaneously energizes the relay 50.which pulls the switches 50a and 50b to the left, as viewed in FIG. 4. As a result the condenser '52 becomes charged. During charging of condenser 52 a charging current flows through the winding of the electromagnet' 14 and therefore said magnet 14 is energized. Thus the magnet 14 pulls the armature 13 to turn the lever 12 away from the disc 7, and in this way the spring 18 returns the exposure "control adjusting device to its zero position. As soon as the charging of condenser 52 is completed, the flow of a charging current through the winding of the electromagnet 14 is terminated and, therefore, the magnet 14 is deenergized although switch Sta remains inits left hand'piosition. Thereafter, if ncces sary, the knob 5 which has returned to its zero position during charging of condenser 52, may be turned to provide a new'adjustment of the exposure control device in accordance wiith the density distribution of the transpar ency which is now in the device. Since the condenser 52 remains in its charged condition and, therefore, the mag,- net 14 is without current, the knob 5 and the remainder of theadjustingdevice remains'in the position in which it has beennewly placed bythe operator, the lever 12 cooperating with the disc 7 for releasably holding the adjusting device in this position.

Also, the movement of the switch Stibby above mentioned energization of the relay 50 discharges the condenser 54 through the magnet 35 and the resistor 57. The

Y resistor 57 is so great that the magnet 35 is not energized and does not pull the armature 38.

When the operatoropens the switch44 so as to turn off the examining light, this switch 44 is again in the position shown in FIGS. 1 and 4 so that the current supply to the relay 50 is cut olf and the switches 50a and 50b automatically return to their starting position shown in FIG. 4. As a result the condenser 52 is discharged through the resistor 53 and without energization of magnet 14,,while the condenser 54 is again charged through the magnet '35. The current chargingthe condenser 54 and flowing through the winding of the electromagnet 35 "momentarily energizes this magnet which thus, at this time, pulls the armature 38 to cause the latch means to be automatically released in the above described manner so that the holder 21 automatically moves to its rest position. As soon as the charging of condenserSS has terminated, magnet 35 is deenergize-d. v v

Now, the light-sensitive copy sheet is placed on the I plate 2 and the holder 21 is again moved to its holding position, whereupon the full downward movement of the lever Z-S'causes the projection 42 thereof to close the switch 43 and thus start the exposure of the copy sheet as well as the operation of the exposure [control device.

' The sWitchesAS, 55 and 59 are nowpulled to the left, 'as

viewed in FIG. 4, by a relay of the exposure control device, so that the darkroom lamp 58 is turned oiT and the lampy45 is energized without the resistor 49 being in its circuit, and at the same time the condenser '54 is discharged through the resistor 56. At the end of the exposure period which is automatically controlled by the exposurecontrol device the switches 48, 55 and 59 automatically return to 'the positions thereof respectively shown in FIG. 4, whereupon the condenser 54 is again charged through the magnet 35 so as to cause this magnet 35 to'again become momentarily energized and thus automatically release the latching means so that the the-adjusting structure of FIG. 2 is not returned to its zero position at this time, any desired number of copies of the transparency in the device may be made without further setting of the knob 5. Only when the transparency is exchanged, so as to require the switch 44 to be closed again, does the knob 5 return automatically to its zero position. Thus/the switch 44 forms an operator controlled device required to be operated in connection with the placing of a new transparency in the copying device, and the operation of the device 44 results in automatic actuation of the return means formed in part by the structure of FIG. 2 for returning this structure to its zero position.

The adjusting structure of FIG. 12 can be returned to its zero position, also through operation of a device other than the switch for energizing the lamp which provides the transparency examining light. For example, when the above-described structure forms part of a contact cop-y device, a movable element which holds the transparency in place may be used to energize the relay 50 for causing the magnet 14 forming also part of the return means to become momentarily energized so as to free the spring 18 for returning the parts 5- 7 to their zero position. Such a construction is shown in FIG. 5.

As may be seen from FIG. 5 the plate 81 carries the housing 82 of a contact copy device. The copy lamp 60 is located in the light tube 61 at the top end of which is located the plate 63 through which the light can pass and which serves as a support for the transparency 62. The turnable holder 64- for the copy sheet is located over the plate 63, and this holder 64 can carry the photoelectric cell of the exposure control device.

edge of the plate 63, as viewed in FIG. 5, is located the springy strip 65 which presses resiliently against the transparency 62 for holding the latter in position, and this strip '65 is carried by the carrier 67 which is turnably supported on the housing 82 by the pivot :pin 66 and which is pivotally connected by a pin 68 with a link 70 whose end distant from carrier 67 is pivotally connected by pin 69 with one end of a ibellcrank 72 supported for turning movement on the stationary pin 71. The arm of the bell crank 72 which is not connected to the link 70 is connected with a bar 73 capable of being moved up and down by the operator through actuation of an unillustrated foot pedal connected with the bar 76 which extends through an opening of the support plate 81. A member '75 is turnably supported by a pin 74 carried by the housing 82 for turning movement over carrier 67 and strip 6'5 to and from the position shown in FIG. 5 where the element 75 serves as a stop for the copy sheet. The knob 5 is mounted on an end wall of the housing 82 and is connected with the above-described structure of FIG. 2 in the manner described above.

In order to energize the magnet 14 of the return means for returning the adjusting structure to its zero position, the embodiments of FIGS. 5 and *6 includes the switch 76 instead of the switch 44. As is shown in FIG. 6 this switch is located in the circuit of the magnet 14. The switch 76 is actuated by the arm 77 of the bell crank 72 when the bar '73 is moved downwardly in order to raise the strip 65, and when the bar 73' is moved downwardly through such a distance that :the notch 78 of the bar 73 moves downwardly beyond the spring 79, which is to say downwardly beyond the position where the bar 73' would he held by cooperation of the spring 79 with the notch 78. In the event that it is desired to maintain the adjustment set by the-knob '5 when changing one transparency for another, then the bar 73 is only moved down until the i the circuit of the magnet 14 includes a normally closed Adjacent the lower lOther devices which form pant of the photographic copying device may be .used to control the switches Ella and 5011 instead of the switch 44- or the switch 76 instead of the strip 65, as long as the devices used for this purpose are required to be operated when the transparency is changed. For example, a movable part of thetransparency carrier -of the enlarger may be used in place of switch 44- to controlswitches 50a and 'Sll b or in place of the strip6'5 to control the switch 76.

'Of course,'the adjusting structure 90f FIG. 2 together with the knob 5 for setting the same, can be located in an additional housing which, for example, forms part of the exposure control device, instead of in the housing which 'forms the support ll or in the housing 82 in the case of the embodiment of FIG. 5. j

' It will be understood that each of the elements described above, or two or more together, may also find a useful applicationin other types of photographic copyingdevices differing from the types described above. 7 While the invention has been illustrated and described as embodied in an adjustable photographic copying device, itis notintended to be limited to the details shown, sincevarious modifications, and structural changes may be made without departi'ng'in any way from the spirit Of-the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this What is claimed as new and desired to be secured by Letters Patent is:

1. In a photographic copying device, in combination,

a light source for illuminating atransparency placed on the photographic copying device;

manually adjustable timing means adjustable between a zero position and a plurality of adjusted positions;

said support for automatically engaging said .laich memher when said holder is in said holding position thereof to prevent said moving means from moving said holder back to said rest position'thereof, said electromagnetic means including an electromagnet, an armature pivotally supported adjacent saidmagnet tolbe turned when the latteris energized, and a pin extending'betweensaid armature and hook member for turning the latter to re lease said latch member when said armature'lturns upon energizing of said electromagnet.

3. Ina device as recited in claim 2, said support being in the form of a housing havinga top wall on which i said holder and latch means arelocated, said electro j magnetic means being located within said housing and said pin extending from the armature in said housing through said top wall into engagement with said hook member on said top wall.

4. In a device as recited in claim 1, said holder being turn ably supported on said support for movement between said rest and holding positions anda manually operable lever connected to said holder for turning movement therewith to be engaged by the operator for moving said holder to said holding position thereof, said latch V invention and, therefore, such adaptations should and are .intended to be comprehended within the meaning and range of equivalence of the following claims.

return means operatively connected to said manually adjustable timing means for returning the latter from "any one of said adjusted positions to said zero position; I

holding means movable between an inoperative position and an'operative position engaging a lightisensi- 'tive printingmateiial placed on said copying device,

saidholdingmeans includingasupport for the light sensitiveprinting material, a holder movably carried by said support for movement between a rest position and; a holding position holding the light sensitive printing material on said supporhlatch means carried by said support and cooperating with said holder for releasably latching the same in said holding position, electromagnetic means, cooperating with Said latch means for actuating thelat ter to release said holder upon energizing of said electromagnetic means, and moving means cooperating with said holder for moving the latter automatically to said rest. position thereof when said latch means is released;

sod

and switch means electrically connected with said light source and said m'eturn means to automatically return said timing means to said zero position upon closing 'of said switch means and said electromagnetic means of said holding means being electrically connected to said switch means to be energized upon'opening of said' switch means so that said holder being moved from said holding to said rest position upon opening of said switch means. I i

2. :In a device as recited in claim 1, said latch means including an arm movable with said holder and carrying a latch member. and a hook member pivotally carried by cmeanscooperating with said lever for releasably holding said holder in said holding position thereof. a

5. In a photographic copying device, in combination,

y-manually operable adjusting means adjustable by, the

operator from a rest position for adjusting a device which controls the exposure of a light-sensitive copy sheet; return means operatively connected with said manually operable adjusting means for returning the same to said rest position, said return means: including an electromagnet which is energized to actuate said return means, and a switch connected in the circuit of said 616C? tromagnet for energizing thelatter; a support for the T transparency which is to be copied; holding means movably carried by the support and cooperating therewith for holding a transparency in a proper position on said support; and actuating means coupled to said holdingsmeans and actuating said switch during movement of said holding means for energizing said electromagnet when one transparency held by said holding means is changed" for another.

6. A photographic copying device comprising, in com- .bination, support means for supporting'a transparency during copying thereof;

copying means for making parency supported by said supportmeans, said copying means including a light source for illuminating a transparency supported on said support means? manually adjustable timing means adjustable between i and actuating means loperatively connected to operated by said operatorcontrolled mechanism during movement thereof and actuating during such movement said return means for returning saidmannally adjustable timing means from any one of said adjusted positions-thereof tosaid zero positioneach L time said mechanism is moved a predetermined distance, said actuating means being independent of said copying means so as to permit successively malt;

ing of copies of one and the same transparency supported on said support means without return of'said Y manually adjustable timing means by said return means tov said zero position,

successively copies of a trans- I 7. An arrangement as defined in claim 6in which said operator controlled mechanism'is constituted by holding engages part 'of said return means for actuating the latter during operation'of saidfholding-means so as to return said manually adjustable timing means from any one of the adjusted positions thereof to said zero position.

8. An arrangement as defined in claim 7 in which said holding means is movable between an inoperative position and .an operative position engaging a transparency placed on said support means, in which said actuating means is movable between two positions thereof and in which during movement of said actuating means from one to the other of said two positions thereof said holding "means is moved from said operative to said inoperative position and said return means is actuated for returning said'manually adjustable timing means from any one of said adjusted positions thereof to said'zero position.

9. An arrangement as defined in claim 7 in which said holding means is movable between an inoperative position and an operative position engaging a transparency placed on said support means and in which said actuating means is movable from a rest position over a first actuating posi- 7 tion to a second actuating position and in which during movement of said actuating means from said rest to said Cit 1t) first actuating position, said holding means is moved from its operative to its inoperative position, while during the movement of said actuating means w from said first to said second actuating position said actuating means engages part of said return means for actuating the latter so as to return said manually adjustable timing means from any one of the adjusted positions thereof to said zero position.

10. An arrangement as defined in claim 6 in which said mechanism is constituted by a switch electrically connected to said light source for energizing the latter when said light source is'used for examining a transparency placed on said suport means and in which saidactuatim D means include switch means electrically connected to said switch and said return means for actuating the latter to automatically return said manually adjustable timing means to said rest position thereof upon closing of said switch.

References Cited in the file of this patent UNITED STATES PATENTS 1,602,051 Sharp Oct. 5, 1926 2,158,903 Knobel May 16, 1939- 2,561,243v Sweet July 17, 1951 2,614,453 MacArthur Oct. 21, 1952 2,660,919 Kleinath Dec. 1, 1953 2,672,787 Schreiber Mar. 23, 1954 2,737,099 'Ohatman .Mar. 6, 1956 

1. IN A PHOTOGRAPHIC COPYING DEVICE, IN COMBINATION, A LIGHT SOURCE FOR ILLUMINATING A TRANSPARENCY PLACED ON THE PHOTOGRAPHIC COPYING DEVICE; MANUALLY ADJUSTABLE TIMING MEANS ADJUSTABLE BETWEEN A ZERO POSITION AND A PLURALITY OF ADJUSTED POSITIONS; RETURN MEANS OPERATIVELY CONNECTED TO SAID MANUALLY ADJUSTABLE TIMING MEANS FOR RETURNING THE LATTER FROM ANY ONE OF SAID ADJUSTED POSITIONS TO SAID ZERO POSITION; HOLDING MEANS MOVABLE BETWEEN AN INOPERATIVE POSITION AND AN OPERATIVE POSITION ENGAGING A LIGHT SENSITIVE PRINTING MATERIAL PLACED ON SAID COPYING DEVICE, SAID HOLDING MEANS INCLUDING A SUPPORT FOR THE LIGHT SENSITIVE PRINTING MATERIAL, A HOLDER MOVABLY CARRIED BY SAID SUPPORT FOR MOVEMENT BETWEEN A REST POSITION AND A HOLDING POSITION HOLDING THE LIGHT SENSITIVE PRINTING MATERIAL ON SAID SUPPORT, LATCH MEANS CARRIED BY SAID SUPPORT AND COOPERATING WITH SAID HOLDER FOR RELEASABLY LATCHING THE SAME IN SAID HOLDING POSITION, ELECTROMAGNETIC MEANS COOPERATING WITH SAID LATCH MEANS FOR ACTUATING THE LATTER TO RELEASE SAID HOLDER UPON ENERGIZING OF SAID ELECTROMAGNETIC MEANS, AND MOVING MEANS COOPERATING WITH SAID HOLDER FOR MOVING THE LATTER AUTOMATICALLY TO SAID REST POSITION THEREOF WHEN SAID LATCH MEANS IS RELEASED; AND SWITCH MEANS ELECTRICALLY CONNECTED WITH SAID LIGHT SOURCE AND SAID RETURN MEANS TO AUTOMATICALLY RETURN SAID TIMING MEANS TO SAID ZERO POSITION UPON CLOSING OF SAID SWITCH MEANS AND SAID ELECTROMAGNETIC MEANS OF SAID HOLDING MEANS BEING ELECTRICALLY CONNECTED TO SAID SWITCH MEANS TO BE ENERGIZED UPON OPENING OF SAID SWITCH MEANS SO THAT SAID HOLDER BEING MOVED FROM SAID HOLDING TO SAID REST POSITION UPON OPENING OF SAID SWITCH MEANS. 